研究人员观察到斑马鱼胚胎中巨噬细胞和新生血液干细胞之间的亲密和特定的相互作用。巨噬细胞的相互作用经常导致细胞质材料的去除和干细胞的分裂,或完全吞噬和干细胞死亡。受压的干细胞被表面的钙网蛋白标记,这刺激了巨噬细胞的相互作用。利用细胞条码,研究人员发现钙网蛋白敲除或胚胎巨噬细胞耗尽减少了建立成体造血功能的干细胞克隆的数量。这项工作支持一种模型,即胚胎巨噬细胞通过监测干细胞质量来决定造血克隆。
据介绍,组织特异性干细胞终生存在,并能分化以维持平衡或转化为癌症。尽管它们很重要,但没有描述新形成的干细胞的质量保障机制。
附:英文原文
Title: Quality assurance of hematopoietic stem cells by macrophages determines stem cell clonality
Author: Samuel J. Wattrus, Mackenzie L. Smith, Cecilia Pessoa Rodrigues, Elliott J. Hagedorn, Ji Wook Kim, Bogdan Budnik, Leonard I. Zon
Issue&Volume: 2022-09-23
Abstract: Tissue-specific stem cells persist for a lifetime and can differentiate to maintain homeostasis or transform to initiate cancer. Despite their importance, there are no described quality assurance mechanisms for newly formed stem cells. We observed intimate and specific interactions between macrophages and nascent blood stem cells in zebrafish embryos. Macrophage interactions frequently led to either removal of cytoplasmic material and stem cell division or complete engulfment and stem cell death. Stressed stem cells were marked by surface Calreticulin, which stimulated macrophage interactions. Using cellular barcoding, we found that Calreticulin knock-down or embryonic macrophage depletion reduced the number of stem cell clones that established adult hematopoiesis. Our work supports a model in which embryonic macrophages determine hematopoietic clonality by monitoring stem cell quality.
DOI: abo4837
Source: https://www.science.org/doi/10.1126/science.abo4837